1. Field of the Invention
The present invention relates to a push-pull type speaker device and a method of manufacturing the same. More particularly, the present invention relates to a push-pull type speaker device and a method of manufacturing the same that can convert magnetic fluxes to a sound signal by disposing an electromagnet at both a north pole and a south pole of a permanent magnet used for the speaker device and enabling a magnetic flux coupled to the north pole and a magnetic flux coupled to the south pole to drive a push-pull type diaphragm.
2. Description of the Related Art
In general, a speaker is a device for receiving an electrical signal and outputting the electrical signal as an audible sound. Specifically, a speaker outputs the audible sound by converting electrical energy from the received electrical signal into mechanical energy using a coil electromagnet. More specifically, the electrical energy is converted into mechanical energy by the coil electromagnet according to Fleming's left-hand rule, in which, when a current flows through a conductor existing within a magnetic field, the conductor receives a force.
When an electrical current signal having several frequencies is applied to the electromagnet, the electromagnet generates a sound pressure at a level that can be detected by the human ear. The electromagnet generates the sound pressure by generating mechanical energy according to current intensity and frequency intensity and enabling a diaphragm attached to the electromagnet to vibrate.
Specifically, a magnetic circuit of the speaker is designed so that a magnetic flux thereof is formed between the electromagnet and a permanent magnet within a frame. Furthermore, the electromagnet is coupled to the diaphragm to generate an electromotive force, driven by an input signal, to vibrate the diaphragm, thereby generating a sound pressure.
The sound pressure generated in the speaker changes according to a position, size, and resonance structure of the speaker and a magnetic flux generating ability between the permanent magnet and the electromagnet. Therefore, when the magnetic flux generated per unit area of the permanent magnet is maximized, an electric signal can be most efficiently converted into a sound signal. However, in a conventional speaker, because an electromagnet is positioned only at one side of a permanent magnet, a limitation in magnetic flux generating ability of an entire magnetic flux of both poles and a speaker diaphragm driving magnetic flux exists.
In order to increase the sound volume of the conventional speaker, a method of securing a resonance space by increasing a diameter and height of the speaker is used. However, this increased bulk of the speaker has lead to a demand for reducing a size while improving a performance of the speaker. Accordingly, there is a need for a speaker device that can convert both a magnetic flux coupled to a north pole and a magnetic flux coupled to a south pole into a sound signal using the north pole and the south pole of a permanent magnet.